Internal and External Secondary Memory Storage

What is secondary memory storage?

• Non-volatile

• Not directly accessible by the CPU

• Used for storing data on a long-term basis

• Classified into: internal and external storage

e.g. hard disk drives (HDDs), solid-state drives (SSDs), optical discs, and flash drives

What are the internal storage?

• Internal SSD

• Internal HDD

• Embedded multimedia cards (eMMCs)

What are Internal Hard disk drives (HDDs)?

• A type of storage device that stores data on magnetic disk platters

• Most common type of internal storage

• Offer high storage capacities and are very reliable

• Can be comparatively slow to access data

• Advantages: large storage capacities, high reliability, and relative affordability.

• Disadvantages: slow data access speeds, and they

What are internal solid state drives

• A type of storage device that uses integrated circuit assmblies to store data persistently, typically using flash memory

• Same pupose as HDDs but are faster and consume less power

  • Have no moving parts leading to quicker access times and lower latency

• non-volatile

• Core storage mechanism is NAND flash memory

• Advantages: rapid access times, higher data transfer rates,

  reduced power consumption, and increased durability due to the lack of mechanical parts

• Disadvantages: more expensive per gigabyte than

  HDDs and may have limited write cycles

What are eMMC?

• aka Embedded multimedia cards

• Type of flash storage found in many low mid-range devices

• Integrates the multimedia card interface, flash memory, and flash memory controller on a small package on the devices mother board

• slower than most SSDs (despite being a solid-state)

• Advantages: fast data access speeds, highly reliable, relativity shock proof

• Disadvantage: greater expense than HDDs and comparatively lower storage capacities than HDDs and SSDs

What are external storage?

• External hard drives

What are external hard drives?

• Come in a variety of sizes and capacities, and they can be used to back up important data, transfer files between computers, or simply store data

• The basic functionality of external HDDs and SSDs is the same as for internal HDDs and SSDs

What are optical drives?

• Once a common type of external storage

• Optical drives are still useful for archiving large amounts of data and for compatibility with older devices

• Advantages: hig storage capaciteis and compatability with older devices

• Disadvantages: slower data access speeds and discs are susecptible to scrataches and dust

What are flash drives?

• aka USB flash drives

• Utilizes NAND flash memory

• Advantages: portability, fast data transfer speeds and

  relative affordability,

• Disadvantage: lower storage capacities than HDDs and SSDs, and they can be susceptible to data loss if not properly handled

What are memory cards?

• small, removable storage devices that are typically used

  in portable devices

• come in a variety of sizes and capacities

• very convenient for transferring files between devices and for backing up data

• utilize NAND flash memory,

• Advantages: portability, compact design, and varied storage capacities.

• Disadvantages: can be lost or damaged easily, and may not be compatible with all devices.

What is a NAS?

• aka Network attached storage

• provide centralized storage for multiple devices on a network

• NAS devices are typically connected to a router, and they can be accessed by any device on the network

• ideal for sharing files, backing up data and storing media files

• NAS typically uses hard disk drives (HDDs), solid state drives (SSDs), or a combination of both in hybrid setups.

• NAS can be configured with RAID (redundant array of independent disks) to protect data against drive failures and ensure data availability.

• NAS can be easily expanded by adding additional hard drives to accommodate growing data needs.

• Advantages: centralized storage, shared access for multiple devices, scalable storage, and a high degree of control for system administrators.

• Disadvantages: more expensive than individual external drives, they require configuration, and they require a network connection.